Signature inflammatory mediators are interleukin (IL)-5, C-C motif chemokine ligand (CCL)-24, monocyte chemoattractant protein (MCP)-4, and vascular cell adhesion molecule (VCAM)-1 in eosinophilic NP, whereas IL-17A, IL-1β, and matrix metallopeptidase (MMP)-9 were detected as signature inflammatory markers in non-eosinophilic NP.
Canonical pathway analysis and gene ontology (GO) evaluation revealed that interleukin (IL)-7, IL-9, IL-17A and IL-22 signaling and neutrophil-mediated immune responses like neutrophil degranulation and activation were significantly increased in CRSwNP compared to control.
The mRNA expression of cytokines, including TSLP, IL-25 and IL-33, as well as interferon (IFN)-γ, IL-4, IL-5, IL-13 and IL-17A in NP and control tissues was examined by qualitative polymerase chain reaction (qPCR).
Eosinophil cation protein (ECP), myeloperoxidase (MPO), IL-25, IL-33, IL-5, IL-13, interferon (IFN)-γ and IL-17 were increased in the cultures, however, only concentrations of MPO, IFN-γ and IL-17 were enhanced in CRSwNP tissues compared to CRSsNP ones.
High levels of IL-17 and its regulatory cytokines in patients with chronic rhinosinusitis with nasal polyposis infected by Aspergillus flavus raise a concern about effective disease management and therapeutic recovery.
We examined the expression of key cytokines (interleukin [IL]-4 IL-5, IL-13, and IL-17A, etc.) and NKX2-1 in NPs with different endotypes and control tissues by immunohistochemistry staining, qualitative polymerase chain reaction (qPCR), enzyme-linked immunosorbent assay (ELISA), and Western blot analysis.
These observations suggest that hypoxia is involved in the pathogenesis of NPs through regulation of IL-17A secretion and HIF1α and HIF2α expression in the NP epithelium.
CRSwNP patients had significantly more tissue IL-17A (9.53 ± 2.71 vs. 1.11 ± 0.43 vs. 0.77 ± 0.07), IL-17F (4.96 ± 1.48 vs. 0.88 ± 0.31 vs. 0.56 ± 0.04), IL-21 (5.55 ± 2.01 vs. 1.60 ± 0.71 vs. 1.53 ± 0.55) and IL-22 (4.73 ± 1.58 vs. 0.70 ± 0.28 vs. 0.88 ± 0.26) producing Th17 cells compared to CRSsNP and control mucosa per mg of tissue, respectively.
IL-6 and sIL-6R levels were not significantly different between the 2 NP groups(P>0.05). pSTAT3 exhibited significantly positive correlations with RORc and IL-17A(P<0.01).
Increased levels of IL-6, pSTAT3, SCOS3, RORc, IL-17A, and CD4(+) RORc(+) cells, and decreased levels of IL-2, pSTAT5, Foxp3, TGF-β1, and CD4(+) Foxp3(+) cells were detected in both NP groups compared to controls (P < .05).
Th17 immunity is involved in the systemic immune responses to allergen in atopic NP and atopy may aggravate NP by stimulating the increase of Th17 population and IL-17A production.
These results indicated that expression of IL-17A was significantly upregulated in NP patients and was more severe in atopic NP patients, suggesting that IL-17A may play an important role in the pathology of NP and atopy may contribute to NP by stimulating the production of IL-17A.